Q. Recently I took 300 milligrams of alpha-lipoic acid after breakfast and I felt weak much of the day. Is this too much or does this mean I shouldn’t take it at all?
A. Alpha-lipoic acid is often referred to as the “universal antioxidant” because it is soluble in both water and fat. This unique quality allows protection against free radical damage both inside and outside the cell, while other antioxidants only provide protection in one area or the other. It is produced naturally in the body, but supplements have been beneficial in certain circumstances.
In Germany, lipoic acid is approved for the treatment of diabetic neuropathy. High doses, 600 milligrams per day, will relieve some of the numbness and also improve blood flow to the peripheral nerves, which will actually stimulate the regeneration of nerve fibers. In addition, it increases the sensitivity of cells to insulin and thus has a direct effect on glucose metabolism.
Because alpha-lipoic acid has been demonstrated to lower blood sugar in diabetics, people with tendency toward hypoglycemia (low blood sugar) should take small amounts throughout the day rather than one large dose. It is likely that 100 milligrams per meal would not provoke the response you experienced with a 300-milligram single dose.
Good food sources of alpha-lipoic acid include spinach, broccoli, beef, brewer’s yeast, and organ meats such as kidney and heart. Some people find these foods unattractive, and since alpha-lipoic acid is a co-factor for a number of important enzymes in addition to its antioxidant properties, a supplement could still be worthwhile.
Alpha-lipoic acid is involved in the conversion of carbohydrates to energy. When sugar is metabolized, it is converted to a substance known as pyruvic acid, which is then used for energy. The enzyme that makes this conversion contains lipoic acid, niacin, and thiamin. If alpha-lipoic acid is inadequate, instead of being used for energy the pyruvate is broken down to lactic acid, and this leads to muscle fatigue.
Alpha-lipoic acid is also recommended for treatment of iron overload, especially when this occurs in association with diabetes mellitus. Iron overload may affect as many as one American out of 10, carrying an increased risk of cancer and heart disease. Alpha-lipoic acid at 300 milligrams per day increases urinary iron excretion and lowers serum iron.
Because alpha-lipoic acid can pass easily into the brain, it has excellent protective effects on brain and nerve tissue. Animals treated with alpha-lipoic acid, for example, suffered less brain damage and had a four times greater survival rate after a stroke than the animals who did not receive this supplement. Human studies have shown that free-radical damage is seen throughout various portions of the brain in Alzheimer’s patients. Antioxidants such as alpha-lipoic acid have been shown in numerous studies to halt or reduce this damage and, in some cases, even reverse the cell damage.
Alpha-lipoic acid has the ability to regenerate other antioxidants like vitamin E, vitamin C, and glutathione so that they can continue to be effective. Research in the last decade has strongly implicated a shortage of antioxidants as the cause of many disorders of aging, including Parkinson’s disease, arthritis, cancer, heart disease, diabetes, and a host of other conditions in addition to those mentioned above. Such a powerful ally to our health should not be dismissed lightly.
This article appears in August 29 • 2003.